android中ListView数据刷新时的同步-优快云博客

public class Main extends BaseActivity {

        private static final String TAG = "tag";
        private static final int STATUS_CHANGE = 0;
        ExpandableListView mElv;
        
        ArrayList<GroupInfo> mGroupArray;
        
        @Override
        public void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                setContentView(R.layout.main);
                mElv = (ExpandableListView) findViewById(R.id.contact_list);
                mStatus = (TextView) findViewById(R.id.setStatus);
                mGroupArray = getIntent().getParcelableArrayListExtra("groupArray");// => 取数据
                mExpandableAdapter = new ExpandableAdapter(this, Main.this);
                mElv.setAdapter(mExpandableAdapter);                
                // 异步对比服务器分组和本地分组
                HandlerThread handlerThread = new HandlerThread("handler_thread");
                handlerThread.start();
                UpdateGroupHandler myHandler = new UpdateGroupHandler(
                                handlerThread.getLooper());
                Message message = myHandler.obtainMessage();
                message.sendToTarget();

                mHandler = new Handler() {
                        public void handleMessage(Message msg) {
                                switch (msg.what) {
                                case STATUS_CHANGE:
                                        // 处理UI更新等操作
                                        updateUI();
                                        break;
                                }
                        };
                };        
        }

        /**
         * 发送消息更新UI
         */
        private void sendMessageToUpdateUI() {
                Message msg = new Message();
                msg.what = STATUS_CHANGE;
                mHandler.sendMessage(msg);// 向Handler发送消息,更新UI
        }

        private void updateUI() {
                // 详细的更新
                mExpandableAdapter.notifyDataSetChanged();// 更新ExpandableListView
        }

        /**
         * 异步刷新分组的handler
         * 
         * @author administrator
         * 
         */
        class UpdateGroupHandler extends Handler {

                public UpdateGroupHandler() {

                }

                public UpdateGroupHandler(Looper looper) {
                        super(looper);
                }

                @Override
                public void handleMessage(Message msg) {
                        ContactsManagerDbAdapter dbAdapter = new ContactsManagerDbAdapter(
                                        Main.this);
                        dbAdapter.open();
                        // =>doSomeThing...
                        mGroupArray = groupList;
                        System.out.println("========数据更新后,刷新listview=========");
                        sendMessageToUpdateUI();
                }

        }

        private class ExpandableAdapter extends BaseExpandableListAdapter {
                Activity activity;
                LayoutInflater layoutInflater;

                public ExpandableAdapter(Activity a, Context context) {
                        activity = a;
                        layoutInflater = (LayoutInflater) context
                                        .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                }

                public Object getChild(int groupPosition, int childPosition) {
                        return mGroupArray.get(groupPosition).getChildList()
                                        .get(childPosition);
                }

                public long getChildId(int groupPosition, int childPosition) {
                        return childPosition;
                }

                public int getChildrenCount(int groupPosition) {
                        return mGroupArray.get(groupPosition).getChildList().size();
                }

                public View getChildView(int groupPosition, int childPosition,
                                boolean isLastChild, View convertView, ViewGroup parent) {
                        // .....
                        return vi;
                }

                public Object getGroup(int groupPosition) {
                        return mGroupArray.get(groupPosition);
                }

                public int getGroupCount() {
                        return mGroupArray.size();
                }

                public long getGroupId(int groupPosition) {
                        return groupPosition;
                }

                public View getGroupView(int groupPosition, boolean isExpanded,
                                View convertView, ViewGroup parent) {
                        GroupInfo groupInfo = mGroupArray.get(groupPosition);
                        String string = groupInfo.getName();
                        convertView = (View) layoutInflater.inflate(R.layout.group_layout,
                                        null);
                        final TextView textView = (TextView) convertView
                                        .findViewById(R.id.groupName);
                        if (textView != null) {
                                textView.setText(string);
                        }
                        return convertView;
                }

                public boolean hasStableIds() {
                        return true;
                }

                public boolean isChildSelectable(int groupPosition, int childPosition) {
                        return true;
                }

        }

}

<groupinfo>代码只是提取的部分,应该没多大影响.<br></groupinfo>

<groupinfo>上面集合mGroupArray存在数据共享,测试多次发现报错有两种:</groupinfo>

<groupinfo>=>1.java.lang.IndexOutOfBoundsException: Invalid location 3, size is 3</groupinfo>

<groupinfo>=>2.The content of the adapter has changed but ListView did not receive a notification. Make sure the content of your adapter is not modified from a background thread, but only from the UI thread.</groupinfo>

<groupinfo>第一个问题,数据同步问题,我弄了下没解决.</groupinfo>

<groupinfo>第二个问题,改变适配器Adapter内容时不要在后台线程中,必须在UI线程中处理</groupinfo>

<groupinfo>我将上面子线程UpdateGroupHandler里的数据更新利用handler提取到了主线程赋值</groupinfo>

<groupinfo>Message.obj = groupList;</groupinfo>

<groupinfo>额,改好后测试多次,发现这两问题都解决了,发现还是对handler理解的不够.</groupinfo>

<groupinfo>!发下更改的代码段:</groupinfo>

<groupinfo><pre name="code" class="java">@Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); mElv = (ExpandableListView) findViewById(R.id.contact_list); mStatus = (TextView) findViewById(R.id.setStatus); mGroupArray = getIntent().getParcelableArrayListExtra("groupArray");// => 取数据 mExpandableAdapter = new ExpandableAdapter(this, Main.this); mElv.setAdapter(mExpandableAdapter); // 异步对比服务器分组和本地分组 HandlerThread handlerThread = new HandlerThread("handler_thread"); handlerThread.start(); UpdateGroupHandler myHandler = new UpdateGroupHandler( handlerThread.getLooper()); Message message = myHandler.obtainMessage(); message.sendToTarget(); mHandler = new Handler() { public void handleMessage(Message msg) { switch (msg.what) { case STATUS_CHANGE: // 处理UI更新等操作 updateUI(msg.obj); break; } }; }; } /** * 发送消息更新UI */ private void sendMessageToUpdateUI(ArrayList<GroupInfo> groupList) { Message msg = new Message(); msg.what = STATUS_CHANGE; msg.obj = groupList; mHandler.sendMessage(msg);// 向Handler发送消息,更新UI } @SuppressWarnings("unchecked") private void updateUI(Object obj) { // 详细的更新 mGroupArray = (ArrayList<GroupInfo>) obj; mExpandableAdapter.notifyDataSetChanged();// 更新ExpandableListView } /** * 异步刷新分组的handler * * @author administrator * */ class UpdateGroupHandler extends Handler { public UpdateGroupHandler() { } public UpdateGroupHandler(Looper looper) { super(looper); } @Override public void handleMessage(Message msg) { ContactsManagerDbAdapter dbAdapter = new ContactsManagerDbAdapter( Main.this); dbAdapter.open(); // =>doSomeThing... System.out.println("========数据更新后,刷新listview========="); sendMessageToUpdateUI(groupList); } }</pre> <br><br></groupinfo>